"""
Genesis AI – Dabur Demand Intelligence Platform
Hugging Face Spaces entry point.

HF Spaces requires:
  - Entry file named app.py
  - App listening on port 7860
  - SDK: docker (we use Flask, not Gradio/Streamlit)
"""

from flask import Flask, request, jsonify, send_from_directory, session
import io, traceback, os, uuid, threading, time

from dabur_baseline_forecast_v2 import run_pipeline, CONFIG

BASE_DIR   = os.path.dirname(os.path.abspath(__file__))
SECRET_KEY = os.environ.get("SECRET_KEY", "dabur-genesisai-hf-2025")
PORT       = int(os.environ.get("PORT", 7860))   # HF Spaces requires 7860

app = Flask(__name__, static_folder=BASE_DIR, static_url_path="")
app.secret_key = SECRET_KEY

# =============================================================================
# USERS  – set via HF Space Secrets for security
#   ANALYST_PASSWORD  /  VIEWER_PASSWORD
# =============================================================================
USERS = {
    "analyst": {
        "password": os.environ.get("ANALYST_PASSWORD", "dabur@analyst"),
        "role": "analyst",
    },
    "viewer": {
        "password": os.environ.get("VIEWER_PASSWORD", "dabur@viewer"),
        "role": "viewer",
    },
}

# =============================================================================
# JOB STORE – background thread per forecast run
# Frontend submits → gets job_id instantly → polls /job/<id> every 5s
# =============================================================================
_jobs: dict        = {}
_latest_forecast   = None
_jobs_lock         = threading.Lock()


def _run_job(job_id: str, file_bytes: bytes, cfg: dict):
    """Pipeline runs in daemon thread. Safe to run long without timeout."""
    global _latest_forecast
    try:
        result = run_pipeline(io.BytesIO(file_bytes), cfg)
        with _jobs_lock:
            _jobs[job_id].update({
                "status":      "done",
                "result":      result,
                "finished_at": time.time(),
            })
        _latest_forecast = result
        print(f"[JOB {job_id[:8]}] Done – {result.get('n_series',0)} series")
    except Exception as e:
        tb = traceback.format_exc()
        print(f"[JOB {job_id[:8]}] ERROR:\n{tb}")
        with _jobs_lock:
            _jobs[job_id].update({
                "status":      "error",
                "error":       str(e),
                "traceback":   tb,
                "finished_at": time.time(),
            })
    # Purge jobs older than 2 hours
    now = time.time()
    with _jobs_lock:
        for jid in [k for k, v in _jobs.items()
                    if v.get("finished_at") and now - v["finished_at"] > 7200]:
            del _jobs[jid]


# =============================================================================
# ROUTES
# =============================================================================

@app.route("/")
def index():
    return send_from_directory(BASE_DIR, "dabur_demand_platform.html")


# ── Auth ───────────────────────────────────────────────────────────────
@app.route("/login", methods=["POST"])
def login():
    data     = request.get_json() or {}
    username = data.get("username", "").strip().lower()
    password = data.get("password", "")
    user     = USERS.get(username)
    if not user or user["password"] != password:
        return jsonify({"status": "error", "message": "Invalid username or password"}), 401
    session["username"] = username
    session["role"]     = user["role"]
    print(f"[AUTH] Login: {username} ({user['role']})")
    return jsonify({"status": "ok", "username": username, "role": user["role"]})


@app.route("/logout", methods=["POST"])
def logout():
    print(f"[AUTH] Logout: {session.get('username','?')}")
    session.clear()
    return jsonify({"status": "ok"})


@app.route("/me", methods=["GET"])
def me():
    if "username" in session:
        return jsonify({"status": "ok",
                        "username": session["username"],
                        "role":     session["role"]})
    return jsonify({"status": "error", "message": "Not logged in"}), 401


# ── Health ─────────────────────────────────────────────────────────────
@app.route("/health", methods=["GET"])
def health():
    return jsonify({"status": "ok", "message": "Genesis AI – running on HF Spaces"})


# ── Submit forecast job ────────────────────────────────────────────────
@app.route("/run", methods=["POST"])
def run():
    if session.get("role") != "analyst":
        return jsonify({"status": "error",
                        "message": "Access denied – analyst role required"}), 403
    if "file" not in request.files:
        return jsonify({"status": "error", "message": "No file uploaded"}), 400

    f = request.files["file"]
    if not f.filename.lower().endswith((".xlsx", ".xls")):
        return jsonify({"status": "error",
                        "message": "Only .xlsx files are supported"}), 400

    cfg = CONFIG.copy()
    try:
        if request.form.get("horizon"):    cfg["forecast_horizon"] = int(request.form["horizon"])
        if request.form.get("season"):     cfg["season_length"]    = int(request.form["season"])
        if request.form.get("cv_horizon"): cfg["cv_horizon"]       = int(request.form["cv_horizon"])
        if request.form.get("top_n"):      cfg["top_n_ensemble"]   = int(request.form["top_n"])
    except ValueError as e:
        return jsonify({"status": "error", "message": f"Invalid config value: {e}"}), 400

    file_bytes = f.read()
    job_id     = str(uuid.uuid4())

    with _jobs_lock:
        _jobs[job_id] = {
            "status":      "running",
            "result":      None,
            "error":       None,
            "started_at":  time.time(),
            "finished_at": None,
        }

    threading.Thread(target=_run_job, args=(job_id, file_bytes, cfg),
                     daemon=True).start()

    print(f"[JOB {job_id[:8]}] Started by {session.get('username','?')}")
    return jsonify({"status": "started", "job_id": job_id})


# ── Poll job status ────────────────────────────────────────────────────
@app.route("/job/<job_id>", methods=["GET"])
def job_status(job_id):
    if "username" not in session:
        return jsonify({"status": "error", "message": "Not logged in"}), 401

    with _jobs_lock:
        job = _jobs.get(job_id)

    if not job:
        return jsonify({"status": "error", "message": "Job not found"}), 404

    if job["status"] == "running":
        return jsonify({"status": "running",
                        "elapsed_seconds": round(time.time() - job["started_at"])})

    if job["status"] == "error":
        return jsonify({"status": "error", "message": job["error"]}), 500

    return jsonify({"status": "done", "result": job["result"]})


# ── Latest forecast for viewer ─────────────────────────────────────────
@app.route("/forecast-result", methods=["GET"])
def forecast_result():
    if "username" not in session:
        return jsonify({"status": "error", "message": "Not logged in"}), 401
    if _latest_forecast is None:
        return jsonify({"status": "empty",
                        "message": "No forecast has been run yet. Ask the analyst to run the pipeline."})
    return jsonify(_latest_forecast)


# =============================================================================
# BOOT
# =============================================================================
if __name__ == "__main__":
    print("=" * 60)
    print("  Genesis AI – Dabur Demand Intelligence Platform")
    print(f"  Running on port {PORT}")
    print(f"  analyst / {USERS['analyst']['password']}  →  Full access")
    print(f"  viewer  / {USERS['viewer']['password']}   →  Output only")
    print("=" * 60)
    app.run(host="0.0.0.0", port=PORT, debug=False, threaded=True)